From: Sherry Sun <sherry.sun@xxxxxxx>
[ Upstream commit 4029dfc034febb54f6dd8ea83568accc943bc088 ]
The LPUART Status Register needs to be cleared when closing the uart
port to get a clean environment when reopening the uart.
Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support")
Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx>
Link: https://lore.kernel.org/r/20221125101953.18753-4-sherry.sun@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/tty/serial/fsl_lpuart.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 5d1c28e094bb2..986ec8323c526 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1796,6 +1796,10 @@ static void lpuart32_shutdown(struct uart_port *port)
spin_lock_irqsave(&port->lock, flags);
+ /* clear status */
+ temp = lpuart32_read(&sport->port, UARTSTAT);
+ lpuart32_write(&sport->port, temp, UARTSTAT);
+
/* disable Rx/Tx DMA */
temp = lpuart32_read(port, UARTBAUD);
temp &= ~(UARTBAUD_TDMAE | UARTBAUD_RDMAE);
--
2.39.2
